Turbo Woe's

[citroenxm]

Dont worry too much about blue smoke. It can indicate oil, but that could be a breather issue, or fuel not quite combusting quite so well..

There will be an electrical valve connection somewhere that will control them. Which state they rest in I dont know on them. My guess is open, then when the Vaccuum comes up then will close.

[rory_perrett]

I'd be tempted to block off the vacuum pipe to the electro valve (Item 10 above) to hopefully restore vacuum to rest of the system and try and "fix" the butterfly valves in the open position then go for a drive and see how it drives.

[rookie]

Thanks guys, that's my first job tomorrow.

Much appreciated

[rory_perrett]

A quick google suggests that the butterflies are normally open and shut to draw more exhaust gas through the EGR system. Perhaps start with just blocking off the vacuum pipe. Not sure how you check if the butterflies are open or closed but then I suppose you've only got to rod positions to try (push or pull) to see if if either one sorts it - good luck.

[rory_perrett]

Thinking aloud now, this comes from something about the 2.2 HDi engine in the C5 but perhaps is relevant and might explain lack of revs, it would also suggest they might be normally closed.

Looks like the later 2.0 HDis have the same system.

If the butterflies are not working properly, this could create all sorts of funny pressures (higher or lower than normal) in the intake system that could be forcing or drawing oil past seals and causing the blue smoke.

"Variable swirl air inlet

The variable swirl system increases the rotational movement of the air in the combustion chamber to ensure that the fuel is completely burned. This ensures high performance and low emissions.
The air intake system includes a helical air duct, causing the air flow to rotate into a vortex (swirl), and a tangential duct providing an axial flow. The tangential duct is fitted with a butterfly valve that opens when the engine reaches a preset speed (2,100 rpm at 80 °C) and the injection rate reaches a preset flowrate (40 mg per cycle).The formation of particles at low engine speeds is reduced as a result of the improved fuel / air mixing in the swirl. At higher engine speeds, more air flows through the tangential duct and the swirl is reduced, thereby optimising airflow into the combustion chamber.The piston tops are machined to provide valve clearances, a central dome and the cavity needed to create the swirl.
The injectors, located centrally in the combustion chamber, ensure uniform fuel spray."

from http://www.citroenet.org.uk/passenger-c ... tech3.html" onclick="window.open(this.href);return false;

[citroenxm]

JUST another thought, though 2001, is it a 1.6 16v or the brilliant 2.0 8v engine??

[rory_perrett]

I don't think this model had the 1.6 engine as a option so I'm assuming 2.0 8v.

[citroenxm]

Yea rory. Dont think the 1.6 was out for another two years or so thinking about it. Silly me...

[djadams]

Have skim read the thread so far, but as diesel engine development is what I do for a living, I figured I'd jump and try and clarify.

A set of flaps in the inlet ports of a diesel engine is port-deactivation variable swirl. As per the quote from a technical manual a few posts up, shutting off one inlet port per cylinder on a modern 16v diesel head is used at low speeds and loads to improve fuel-air mixing. With the actuator diaphragm torn, I don't know in this case whether the flaps would default open or shut, but either way you have problems. Defaulting open would cause a lack of "swirl" motion in the cylinders at low engine speeds and loads and could very well result in poor combustion and "white smoke" of unburnt fuel ("HC") out of the back at low engine speeds. However, if they default closed, then at higher engine speeds they could well restrict airflow and cause poor combustion and that might cause white smoke at higher revs - and I think that could be what is happening in your case. With the torn diaphragm, the system will be losing vacuum when it's trying to move the actuator, so it would not be able to hold the wastegate shut which would give you very poor boost performance. Either way, you will need to replace the damaged actuator on the swirl flaps to get the engine running properly.

The benefit of the system (when it's working!) is that it allows the engine to run a higher flow set of injectors to get the performance you want when you put your foot down without suffering bad HC and CO emissions when tootling around town. The variable swirl flaps don't reduce airflow as such when they're working properly (they're not a choke) they just make it flow into the cylinder in a different way and help reduce HC, CO and smoke emissions.

[rookie]

Very informative djadams !
That would explain why, when I was driving the car, it drove just like a vehicle without a turbo, in fact, it drove worse.
There were no clouds of smoke (though there was the constant flow of blue smoke) but it was so sluggish I could possibly have ran faster when accelerating.

I have only had this car for about a week and started off by investigating why the brakes "Lock On when being driven, and worse, why they lock on when the car was being towed with the battery disconnected.

I am beginning to wonder if the vacuum built up (or lost) when the engine is running is somehow affecting the brakes.

However that problem is the next on the list when I get it running correctly.

much obliged

[citroenxm]

Course it will be. The brakes are vaccuumm servo assisted. No vac no servo crap brakes.. all related.

[sparksie]

Hmmm.
Well, no vacuum would generally make the brakes harder to activate, so the description "crap brakes" is sort of appropriate.
However, that is not the symptom described by the OP, so the generalisation "all related" won't be correct here!
In this case we have brakes that are coming on all by themselves.
If we were talking railways, or HGVs, then maybe, but not on a car or light van.
On those the brakes are by default not applied and need input from the driver to apply them, albeit with assistance from the servo.
I'm following this thread with interest, because I'm at a loss to come up with a plausible cause.
I've been toying with the possibility of a catastrophic failure in the servo (eg broken diaphragm return spring), or perhaps the wrong servo, or push rod having been fitted by a previous owner, but I think these latter two would probably be noticeable. A dud servo would probably feel wrong at the pedal, too. Yet the OP made no mention of any evidence of work having been done around the servo, nor of anything unusual about the pedal.
Most mysterious and I can't wait for the solution.

[rookie]

Just a quick update on the turbo problem.
Have ordered the new vac valve (item 8) it arrives tomorrow.
In the meantime, I turned the arm that the vac valve fits onto, into it's fully open position and went for a drive.

The car went like the clappers though there was still evidence of a small amount of blue smoke. I assume that whereas before it was being caused by not enough air getting through at high revs, it is now too much air getting through at low revs.

As for the brake problem, I drove the car for about 4 miles with no problem evident (though I don't know how long the previous owner had to drive it crate the problem).
The only work that I can see that has recently been done on the brakes is a brand new master cylinder fitted to the servo.

When the brakes locked up whilst it was being towed, it happened after I had started the engine and drove the car off the sellers driveway.
I am assuming that created vacuum in the system, then less than half an hour later, under tow, the brakes locked on, is it plausible that the vacuum leak on the intake butterfly actuator could have caused the brakes to lock on ?

I am obviously missing something really obvious, can't wait until it whacks me in the face.

[rory_perrett]

Good to know that getting the engine sorted is going in the right direction.
When you say the brakes locked up when being towed did they just come on on their own or was someone in the vehicle operating the brakes. Ie they suddenly failed to release?

[rookie]

Hi Rory

I was about 20 minutes or so into the tow.
The battery was disconnected, the ignition was on and I was using an "A Frame" to tow with. No one was inside the car whilst it was being towed, handbrake was off.

They locked up solid, all 4 wheels though the front wheels were hotter than the rear but ALL were smoking hot.
I undid the bleed screws and just let the oil run out and the brakes came off (the oil was under pressure when bleed screws loosened.)

????????????????????????????????????????????????????????????????????????????